Trying to get the cylinder head off my TY250. I have beat on it with a rubber mallet and gently pryed on it with a pry bar but it won't budge. Any advise on how to get it loose?

Might try a dead blow hammer (a rubber mallet filled with lead shot) or a regular hammer against a piece of soft wood.

A good way to start a head moving is to put the piston up near TDC, fill the combustion chamber with oil, refit the spark plug then rock the bike back and forth in top gear.

Once it is moving but it is still tight, suspend the bike off the ground a bit by the head and gently bump the bike downwards. Gravity will do the hard work for you.

Sounds like a lot of work!

Heads with copper gaskets usually come off fairly easy.

Asbestos gaskets hold on a good deal better.

Some people will use goo or glue, which complicates matters.

If I get a stubborn one, I stick a big, fat screwdriver between the cylinder and the head and twist it...with a wrench, if necessary.

Use some heat from a torch and things may loosen up a bit.

If you feel that you must pry with the screwdriver, pry UP, with the screwdriver pushed in as far as you can, as you'll be prying where the most meat is.

If you pry down, you'll have pressure against the outside of a cylinder fin, and it will snap right off.

Finally got it off. Been on since '74. It ended up being one of those things you just need to walk away from for a while and come back to it later.